It looks like Ford will continue to have V8s for the foreseeable future, but they are getting smaller. This makes sense as consumers have a perception that V8's are the way to go with trucks. They want a V8, and power, with this clashing with the need to make them lighter and more efficient due government mandates:

Ford to produce 4.8L V8 in Canadian plant
http://www.reuters.com/article/canada-autos-ford-motor-idUSL1N1D41MC

It all translates to better technology and fuel economy, but I bet the price tag goes up significantly as well.